Circle cutting machine



De@ 9 1941- w. c. DoRNEzRocK CIRCLE CUTTING MACHINE Filed May 2, 1941 v v\1 5 m 1.. @h Il o l F. l A c L, Anw .\l\\ 'fj7 o \\A 5 FJ Il u I m I| M m Patented Dec. 9, 1941 UNITED STATES PATENT` OFFICE CIRCLE CUTTING MACHINE William C. Dornbrock, rDetrc'it,` Mich.. Application May 2, 1941, serial No. 391,553 `4 Claims'. `(C1. 164-71) I A A The present invention `pertains to a novel machine for cutting circles or 'rings out of metal and is designed primarily for yuse by the printing industry. Y 'l Y In newspaper and other advertisments of a printed nature, printed circles are-often used for ornamental and display effects. The printing character of the desired 'external' and internal dimensions is often not at hand, and it is customary Vto make the character to order in the printing plant. rllljieexternal and-internal circumferences are scribed on a blank of type metal which is next roughly cut out along these circumferences and finally finished to size by iiling. 'I'he operation does not warrant the in- Istallation of an expensive machine, and even in large newspaper plants, circular characters are made in the manner above described.

The object of this invention is to provide a simple and inexpensive machine for the purpose described, as well as one that is capable of cutting a double circle or more than one circle simultaneously. The machine consists essentially of a turntable aon which the blank is secured, with a device for elevating the blank against one or more fixed cutting tools. It is evident that the machine herein described is not limited to the cutting of printing characters but is obviously suitable for cutting circles from various metals, wood and compositions for numerous purposes. The tools are however adjustable radially from the center of rotation of the turntable and are indexed along a fixed printers scale. Preferably, the tool is not permitted to cut entirely through the blank and leaves a thinness of metal which enables breaking off the circle by hand.

The invention is fully disclosed by way of example in the following description and in the accompanying drawing in which:

Figure 1 is a vertical elevation of the device;

Figure 2 is a detail vertical section;

Figure 3 is a section on the line 3-3 of Figure 2;

Figure 4 is Figure 1;

Figure 5 is Figure 1 and,

Figure 6 is a section on the line Figure 1.

Reference to these views will now be made by use of like characters which are employed to designate corresponding parts throughout.

The machine is built in a frame I of appropriate construction in which is journalled a a section on the line 4 4 of a section on the line 5-5 of vertical shaft 2. v`A rvmotor 3 drives through a gearbox 4.

On the upper end of the shaft I is splined a block 5 rcarrying a turntable 6. Beneath the block, a sleeve 'I is slidably mounted on shaft and receives a fork 8. FromA the fork is extended a'lever I0 fulcrumed in the frame at II' and extending beyond one side of the frame, as illustrated in Figures 1 and 4.

The frame Iincludes a pair of posts or uprights 9 at opposite sides of the turntable 6l The posts support a pair of rods I2 vvone above the other and crossing the projected axis of the shaft the shaft 2. The rods support one or more tool holders, each of which consists of Va pair of blocks I3 adapted to be clamped on the rods by a screw I4. One of the blocks extends downwardly beyond the other and is adapted to receive a cutting tool I5.

Above the rods I2, the posts II support a bar I6 to which is secured a printers scale I'I graduated in twelfths of an inch outwardly from the projected axis of the shaft 2.

The surface of the turntable 6 is formed with a suitable number of radial grooves I8 in which screw clamps I9 are mounted. A blank 20 of type metal is adapted to be secured between the clamps.

A bracket 2I is provided on the frame directly over the exposed end of the lever I0. This end is adapted to be engaged by a thumbscrew 22 in the bracket 2l, whereby the turntable 6 may be worked up and down at will through the fork 8 and sleeve 1.

The upper end of each pair of blocks I3 carries an index finger 23 in line with the tool I5 and adjacent to the scale I1. By this means, the tool is set at the desired distance from the center of rotation of the shaft 2 and turntable 6. It will be understood that the tool holder can be released for sliding on the rods I2 by means of the screw I4 and similarly tightened in place. The tool or tools not to be used are rendered idle by releasing the respective holders entirely from the rods I2 and setting them on the rods in a reverse position as shown in Figure 1.

In cutting the first circle out of the blank 20, it is preferable to use two tools set respectively at the internal and external radii for simultaneous cutting.v During rotation of the turntable, the screw 22 is operated to bring the blank 20 against the tools in the manner previously described. The grooves cut by the tools are of such depth as to leave a thickness of metal from which the circle can be broken off by hand. Any burrs remaining on the severed circle can rreadily be removed When they iile.`

Additional circles can be cut out of the blank at the same time by using additional tools.

p Although a specific embodiment of the invention has been illustrated and described, it will be y 1. A machine of the character described comprising a frame, a shaft journalled verticallyV Y therein, a turntable slidably carried by said.

shaft, a lever fulcrumed in said frame and a horizontal rod ysupported in said frame over said turntable and passing substantiallythrough the projected axis of said'shaft,^"and a 'toolf holder adjustably mounted on saidfrod;

2. `A ma'chme' ofthe character: described comprising a frame; a shaft,journalldve'rti` cally therein', a turntable carried by said shaft, a lever fulcrumed in said frame and'adapted to impartA vertical4 movement to said 'turntable during rotation of said shaft', means for sup-l porting a Work piece oni said turntable, a hori zontal rod supported in said frame -over said turntable and passing substantially through the projected axis of said shaft,` and a tool holder "15 adapted to impart vertical movementtosaid turntable during rotation of said shaft, means" for supporting a work piece o'ns'aid t'ilr'ntable;

adjustably mounted on said rod, a scale mounted adjacent to said rod, and an indexing member on said holder and cooperating lwith said scale.

3. A machine of the character described comprising a frame, a shaft journalled vertically therein, a turntable carried by said shaft, a lever fulcrumed in said frame and adapted to impart vertical movement toy said turntable during rotation of said shaft, a screw mounted in said frame and bearing againstsaid lever .to actuate the same, means for ysupporting a work piece on said turntable, a horizontal rod supported in said frame over said turntable and passing substantially through the projected axis of said shaft, and avtool holder adjustably mounted on said rod.

4. A machine of the character described comfprising"` a frame, a yshaft journalled vertically l therein, a turntable carried by said shaft, -a

lever fulc'rumed in said frame and adapted to l impart verticall movement to said turntable duringrotation `of said shaft, a screw mounted in saidframe and bearing against said lever to actuate the same, means for supporting a Work Y piece on said turntable, a horizontalV rod sup-- portedl inxsaid frame over said turntable and passing substantially through the projected axis of saidshaft, Yand a tool holder adjustably mounted on said rod, a scale mounted adjacent to said rod, and an indexing member on said holder and cooperating with said scale. Y

' WILLIAM C. DORNBROCK. 

